王昕玥 张强 崔志松 兰雪 李翠花 朱琳 王胡振

摘 要：在鉆井过程中，如果地层孔隙中流体的压力小于钻井液液柱压力，会发生地层被钻井液侵入，引起地层污染的后果。这会大大影响油气井的产能，我们只有理解和掌握钻井液渗滤的污染机理，才能有效的进行防治。在油气井投产之前，一般会采用酸化、压裂的方法解堵，为了确保解堵措施安全高效，需要精准地确定钻井液的伤害程度和侵入深度。数值模拟在研究钻井液渗滤问题上应用非常广泛。基于有限元的数值模拟的方法研究地层渗透率，泥饼渗透率和钻井时间对钻井液渗滤的影响。通过对相关算例进行分析，系统的概括出钻井液渗滤的影响因素。结果表明：地层渗透率越低，钻井液沿水平井筒渗滤越困难；泥饼渗透率越低，钻井液的侵入深度越小，钻井时间越长钻井液沿水平井筒渗滤越多，侵入的深度越大。

关 键 词：钻井液侵入；水平井；地层污染

中图分类号：TE 357 文献标识码： A 文章编号： 1671-0460（2015）07-1515-04

Study on Drilling Fluid Percolation Along Horizontal Well

WANG Xin-yue1，2，ZHANG Qiang3，CUI Zhi-song3，LAN Xue4，LI Cui-hua5，ZHU Lin6，WANG Hu-zhen1，2

（1. Northeast Petroleum University， Heilongjiang Daqing 163318，China；

2. China Petroleum Group Company Reservoir Reconstruction Key Laboratory， Heilongjiang Daqing 163318，China

3. PetroChina Xinjiang Company Exploration and Research Institute， Xinjiang Kelamayi 834000，China

4. Jilin Oilfield Company Exploration and Research Institute， Jilin Songyuan 138000，China

5. Xinjiang Oilfield Company Baikouquan Oil Production Factory， Xinjiang Kelamayi 834000，China

6. Daqing Oilfield Company the Fourth Oil Production Factory， Heilongjiang Daqing 163511，China）

Abstract： In the process of drilling， if the formation pore fluid pressure is less than drilling fluid column pressure， formation pollution caused by drilling fluid invasion will happen. This will greatly affect the capacity of oil and gas wells， the pollution mechanism of drilling fluid percolation must be understood and mastered in order to carry out effective prevention and control. Before the oil and gas well production， blockage removal methods of acidification and fracturing are usually adopted. In order to ensure blockage removal measures to be safe and effective， the damage degree and the invasion depth of drilling fluid need be accurately determined. The numerical simulation has been widely used in research on drilling fluid percolation. In this paper， based on the finite element method of numerical simulation， effect of formation permeability， mud cake permeability and drilling time on drilling fluid percolation was studied. Through analysis of relevant examples， the influence factors of drilling fluid percolation were summed up. The results show that， the lower the formation permeability， the more difficult the drilling fluid percolation along the horizontal wellbore； The lower the mud cake permeability， the smaller the invasion depth of drilling fluid； the longer the drilling time， the more the drilling fluid percolation along the horizontal wellbore， the greater the depth of invasion.

Key words： Drilling fluid invasion； Horizontal well； Formation pollution

过去的10年里水平井得到了飞速的发展，因为它可以使泄油面积大大的增加，从而使采油速度更快更有效。但是，随着水平井段的增加排水区域和井筒都将增加，这将延长钻井液的暴露时间和增加钻井液与地层的接触面积。因此，由钻井液的侵入而带来的一些污染会在很大程度上减少水平井的产量[1-3]。为了尽可能减少或避免钻井液对油气层的造成伤害，一般会在油气井投产之前采用酸化压裂等解堵措施，用來恢复并提高油气井产能。……